diff --git a/llvm/lib/CodeGen/RegisterCoalescer.cpp b/llvm/lib/CodeGen/RegisterCoalescer.cpp index cab284f1028b..60c1b2b9302c 100644 --- a/llvm/lib/CodeGen/RegisterCoalescer.cpp +++ b/llvm/lib/CodeGen/RegisterCoalescer.cpp @@ -15,8 +15,9 @@ #define DEBUG_TYPE "regcoalescing" #include "RegisterCoalescer.h" -#include "VirtRegMap.h" #include "LiveDebugVariables.h" +#include "RegisterClassInfo.h" +#include "VirtRegMap.h" #include "llvm/Pass.h" #include "llvm/Value.h" @@ -75,6 +76,127 @@ VerifyCoalescing("verify-coalescing", cl::desc("Verify machine instrs before and after register coalescing"), cl::Hidden); +namespace { + class RegisterCoalescer : public MachineFunctionPass { + MachineFunction* mf_; + MachineRegisterInfo* mri_; + const TargetMachine* tm_; + const TargetRegisterInfo* tri_; + const TargetInstrInfo* tii_; + LiveIntervals *li_; + LiveDebugVariables *ldv_; + const MachineLoopInfo* loopInfo; + AliasAnalysis *AA; + RegisterClassInfo RegClassInfo; + + /// JoinedCopies - Keep track of copies eliminated due to coalescing. + /// + SmallPtrSet JoinedCopies; + + /// ReMatCopies - Keep track of copies eliminated due to remat. + /// + SmallPtrSet ReMatCopies; + + /// ReMatDefs - Keep track of definition instructions which have + /// been remat'ed. + SmallPtrSet ReMatDefs; + + /// joinIntervals - join compatible live intervals + void joinIntervals(); + + /// CopyCoalesceInMBB - Coalesce copies in the specified MBB, putting + /// copies that cannot yet be coalesced into the "TryAgain" list. + void CopyCoalesceInMBB(MachineBasicBlock *MBB, + std::vector &TryAgain); + + /// JoinCopy - Attempt to join intervals corresponding to SrcReg/DstReg, + /// which are the src/dst of the copy instruction CopyMI. This returns + /// true if the copy was successfully coalesced away. If it is not + /// currently possible to coalesce this interval, but it may be possible if + /// other things get coalesced, then it returns true by reference in + /// 'Again'. + bool JoinCopy(MachineInstr *TheCopy, bool &Again); + + /// JoinIntervals - Attempt to join these two intervals. On failure, this + /// returns false. The output "SrcInt" will not have been modified, so we + /// can use this information below to update aliases. + bool JoinIntervals(CoalescerPair &CP); + + /// AdjustCopiesBackFrom - We found a non-trivially-coalescable copy. If + /// the source value number is defined by a copy from the destination reg + /// see if we can merge these two destination reg valno# into a single + /// value number, eliminating a copy. + bool AdjustCopiesBackFrom(const CoalescerPair &CP, MachineInstr *CopyMI); + + /// HasOtherReachingDefs - Return true if there are definitions of IntB + /// other than BValNo val# that can reach uses of AValno val# of IntA. + bool HasOtherReachingDefs(LiveInterval &IntA, LiveInterval &IntB, + VNInfo *AValNo, VNInfo *BValNo); + + /// RemoveCopyByCommutingDef - We found a non-trivially-coalescable copy. + /// If the source value number is defined by a commutable instruction and + /// its other operand is coalesced to the copy dest register, see if we + /// can transform the copy into a noop by commuting the definition. + bool RemoveCopyByCommutingDef(const CoalescerPair &CP,MachineInstr *CopyMI); + + /// ReMaterializeTrivialDef - If the source of a copy is defined by a + /// trivial computation, replace the copy by rematerialize the definition. + /// If PreserveSrcInt is true, make sure SrcInt is valid after the call. + bool ReMaterializeTrivialDef(LiveInterval &SrcInt, bool PreserveSrcInt, + unsigned DstReg, unsigned DstSubIdx, + MachineInstr *CopyMI); + + /// shouldJoinPhys - Return true if a physreg copy should be joined. + bool shouldJoinPhys(CoalescerPair &CP); + + /// isWinToJoinCrossClass - Return true if it's profitable to coalesce + /// two virtual registers from different register classes. + bool isWinToJoinCrossClass(unsigned SrcReg, + unsigned DstReg, + const TargetRegisterClass *SrcRC, + const TargetRegisterClass *DstRC, + const TargetRegisterClass *NewRC); + + /// UpdateRegDefsUses - Replace all defs and uses of SrcReg to DstReg and + /// update the subregister number if it is not zero. If DstReg is a + /// physical register and the existing subregister number of the def / use + /// being updated is not zero, make sure to set it to the correct physical + /// subregister. + void UpdateRegDefsUses(const CoalescerPair &CP); + + /// RemoveDeadDef - If a def of a live interval is now determined dead, + /// remove the val# it defines. If the live interval becomes empty, remove + /// it as well. + bool RemoveDeadDef(LiveInterval &li, MachineInstr *DefMI); + + /// RemoveCopyFlag - If DstReg is no longer defined by CopyMI, clear the + /// VNInfo copy flag for DstReg and all aliases. + void RemoveCopyFlag(unsigned DstReg, const MachineInstr *CopyMI); + + /// markAsJoined - Remember that CopyMI has already been joined. + void markAsJoined(MachineInstr *CopyMI); + + /// eliminateUndefCopy - Handle copies of undef values. + bool eliminateUndefCopy(MachineInstr *CopyMI, const CoalescerPair &CP); + + public: + static char ID; // Class identification, replacement for typeinfo + RegisterCoalescer() : MachineFunctionPass(ID) { + initializeRegisterCoalescerPass(*PassRegistry::getPassRegistry()); + } + + virtual void getAnalysisUsage(AnalysisUsage &AU) const; + + virtual void releaseMemory(); + + /// runOnMachineFunction - pass entry point + virtual bool runOnMachineFunction(MachineFunction&); + + /// print - Implement the dump method. + virtual void print(raw_ostream &O, const Module* = 0) const; + }; +} /// end anonymous namespace + char &llvm::RegisterCoalescerPassID = RegisterCoalescer::ID; INITIALIZE_PASS_BEGIN(RegisterCoalescer, "simple-register-coalescing", diff --git a/llvm/lib/CodeGen/RegisterCoalescer.h b/llvm/lib/CodeGen/RegisterCoalescer.h index 7ba6ef76e7d4..a2957f501e69 100644 --- a/llvm/lib/CodeGen/RegisterCoalescer.h +++ b/llvm/lib/CodeGen/RegisterCoalescer.h @@ -12,156 +12,15 @@ // //===----------------------------------------------------------------------===// -#include "RegisterClassInfo.h" -#include "llvm/Support/IncludeFile.h" -#include "llvm/CodeGen/LiveInterval.h" -#include "llvm/ADT/SmallPtrSet.h" - #ifndef LLVM_CODEGEN_REGISTER_COALESCER_H #define LLVM_CODEGEN_REGISTER_COALESCER_H namespace llvm { - class MachineFunction; - class RegallocQuery; - class AnalysisUsage; class MachineInstr; class TargetRegisterInfo; class TargetRegisterClass; class TargetInstrInfo; - class LiveDebugVariables; - class VirtRegMap; - class MachineLoopInfo; - - class CoalescerPair; - - /// An abstract interface for register coalescers. Coalescers must - /// implement this interface to be part of the coalescer analysis - /// group. - class RegisterCoalescer : public MachineFunctionPass { - MachineFunction* mf_; - MachineRegisterInfo* mri_; - const TargetMachine* tm_; - const TargetRegisterInfo* tri_; - const TargetInstrInfo* tii_; - LiveIntervals *li_; - LiveDebugVariables *ldv_; - const MachineLoopInfo* loopInfo; - AliasAnalysis *AA; - RegisterClassInfo RegClassInfo; - - /// JoinedCopies - Keep track of copies eliminated due to coalescing. - /// - SmallPtrSet JoinedCopies; - - /// ReMatCopies - Keep track of copies eliminated due to remat. - /// - SmallPtrSet ReMatCopies; - - /// ReMatDefs - Keep track of definition instructions which have - /// been remat'ed. - SmallPtrSet ReMatDefs; - - /// joinIntervals - join compatible live intervals - void joinIntervals(); - - /// CopyCoalesceInMBB - Coalesce copies in the specified MBB, putting - /// copies that cannot yet be coalesced into the "TryAgain" list. - void CopyCoalesceInMBB(MachineBasicBlock *MBB, - std::vector &TryAgain); - - /// JoinCopy - Attempt to join intervals corresponding to SrcReg/DstReg, - /// which are the src/dst of the copy instruction CopyMI. This returns true - /// if the copy was successfully coalesced away. If it is not currently - /// possible to coalesce this interval, but it may be possible if other - /// things get coalesced, then it returns true by reference in 'Again'. - bool JoinCopy(MachineInstr *TheCopy, bool &Again); - - /// JoinIntervals - Attempt to join these two intervals. On failure, this - /// returns false. The output "SrcInt" will not have been modified, so we can - /// use this information below to update aliases. - bool JoinIntervals(CoalescerPair &CP); - - /// AdjustCopiesBackFrom - We found a non-trivially-coalescable copy. If - /// the source value number is defined by a copy from the destination reg - /// see if we can merge these two destination reg valno# into a single - /// value number, eliminating a copy. - bool AdjustCopiesBackFrom(const CoalescerPair &CP, MachineInstr *CopyMI); - - /// HasOtherReachingDefs - Return true if there are definitions of IntB - /// other than BValNo val# that can reach uses of AValno val# of IntA. - bool HasOtherReachingDefs(LiveInterval &IntA, LiveInterval &IntB, - VNInfo *AValNo, VNInfo *BValNo); - - /// RemoveCopyByCommutingDef - We found a non-trivially-coalescable copy. - /// If the source value number is defined by a commutable instruction and - /// its other operand is coalesced to the copy dest register, see if we - /// can transform the copy into a noop by commuting the definition. - bool RemoveCopyByCommutingDef(const CoalescerPair &CP,MachineInstr *CopyMI); - - /// ReMaterializeTrivialDef - If the source of a copy is defined by a trivial - /// computation, replace the copy by rematerialize the definition. - /// If PreserveSrcInt is true, make sure SrcInt is valid after the call. - bool ReMaterializeTrivialDef(LiveInterval &SrcInt, bool PreserveSrcInt, - unsigned DstReg, unsigned DstSubIdx, - MachineInstr *CopyMI); - - /// shouldJoinPhys - Return true if a physreg copy should be joined. - bool shouldJoinPhys(CoalescerPair &CP); - - /// isWinToJoinCrossClass - Return true if it's profitable to coalesce - /// two virtual registers from different register classes. - bool isWinToJoinCrossClass(unsigned SrcReg, - unsigned DstReg, - const TargetRegisterClass *SrcRC, - const TargetRegisterClass *DstRC, - const TargetRegisterClass *NewRC); - - /// UpdateRegDefsUses - Replace all defs and uses of SrcReg to DstReg and - /// update the subregister number if it is not zero. If DstReg is a - /// physical register and the existing subregister number of the def / use - /// being updated is not zero, make sure to set it to the correct physical - /// subregister. - void UpdateRegDefsUses(const CoalescerPair &CP); - - /// RemoveDeadDef - If a def of a live interval is now determined dead, - /// remove the val# it defines. If the live interval becomes empty, remove - /// it as well. - bool RemoveDeadDef(LiveInterval &li, MachineInstr *DefMI); - - /// RemoveCopyFlag - If DstReg is no longer defined by CopyMI, clear the - /// VNInfo copy flag for DstReg and all aliases. - void RemoveCopyFlag(unsigned DstReg, const MachineInstr *CopyMI); - - /// markAsJoined - Remember that CopyMI has already been joined. - void markAsJoined(MachineInstr *CopyMI); - - /// eliminateUndefCopy - Handle copies of undef values. - bool eliminateUndefCopy(MachineInstr *CopyMI, const CoalescerPair &CP); - - public: - static char ID; // Class identification, replacement for typeinfo - RegisterCoalescer() : MachineFunctionPass(ID) { - initializeRegisterCoalescerPass(*PassRegistry::getPassRegistry()); - } - - /// Register allocators must call this from their own - /// getAnalysisUsage to cover the case where the coalescer is not - /// a Pass in the proper sense and isn't managed by PassManager. - /// PassManager needs to know which analyses to make available and - /// which to invalidate when running the register allocator or any - /// pass that might call coalescing. The long-term solution is to - /// allow hierarchies of PassManagers. - virtual void getAnalysisUsage(AnalysisUsage &AU) const; - - virtual void releaseMemory(); - - /// runOnMachineFunction - pass entry point - virtual bool runOnMachineFunction(MachineFunction&); - - /// print - Implement the dump method. - virtual void print(raw_ostream &O, const Module* = 0) const; - }; /// CoalescerPair - A helper class for register coalescers. When deciding if /// two registers can be coalesced, CoalescerPair can determine if a copy